DasGupta, ShamikWaddell, Scott2022-08-232022-08-232008-11-112011-05-20Curr Biol. 2008 Nov 11;18(21):1668-74. Epub 2008 Oct 23. <a href="http://dx.doi.org/10.1016/j.cub.2008.08.071">Link to article on publisher's site</a>0960-9822 (Linking)10.1016/j.cub.2008.08.07118951022https://hdl.handle.net/20.500.14038/33184A unifying feature of mammalian and insect olfactory systems is that olfactory sensory neurons (OSNs) expressing the same unique odorant-receptor gene converge onto the same glomeruli in the brain [1-7]. Most odorants activate a combination of receptors and thus distinct patterns of glomeruli, forming a proposed combinatorial spatial code that could support discrimination between a large number of odorants [8-11]. OSNs also exhibit odor-evoked responses with complex temporal dynamics [11], but the contribution of this activity to behavioral odor discrimination has received little attention [12]. Here, we investigated the importance of spatial encoding in the relatively simple Drosophila antennal lobe. We show that Drosophila can learn to discriminate between two odorants with one functional class of Or83b-expressing OSNs. Furthermore, these flies encode one odorant from a mixture and cross-adapt to odorants that activate the relevant OSN class, demonstrating that they discriminate odorants by using the same OSNs. Lastly, flies with a single class of Or83b-expressing OSNs recognize a specific odorant across a range of concentration, indicating that they encode odorant identity. Therefore, flies can distinguish odorants without discrete spatial codes in the antennal lobe, implying an important role for odorant-evoked temporal dynamics in behavioral odorant discrimination.en-USJournal Articlehttps://escholarship.umassmed.edu/gsbs_sp/17222022733gsbs_sp/1722